Electromagnetic (EM) wave polarizing structure and method for providing polarized electromagnetic (EM) wave

Abstract

The EM polarizing structure contains a two dimensional planar variation structure, having medium nodes regularly distributed as a two dimensional planar photonic unit lattice cell array on a plane. Each of the photonic unit lattice cells has an operation axis and is identical at each lattice point, which passes a diagonal of photonic unit lattice cell. The medium nodes within each planar photonic unit lattice cell are distributed asymmetrical with respect to the operation axis direction and identical at each lattice point. The EM polarizing structure is used to modulate an input EM wave around an operation frequency of the photonic band associated with the EM wave polarizing structure. Thus a corresponding output EM wave becomes polarized. Moreover, the EM wave polarizing structure can be integrated with an EM wave emitting source. Thus an output EM wave from the device is polarized.

1. An electromagnetic (EM) wave polarizing structure, comprising:
 a two dimensional planar pattern structure having medium nodes, wherein said medium nodes are regularly distributed as a plurality of planar photonic unit lattice cells being two-dimensional on a plane, each of said planar photonic unit lattice cells is identical and has an operation axis, of which direction passes a diagonal of said photonic unit lattice cell, and said medium nodes within each of said photonic unit lattice cells distributed asymmetrical with respect to said operation axis direction are identical at each lattice point, wherein each of said photonic unit lattice cells is an in-equilateral parallelogram, 
 wherein said EM wave polarizing structure thus processes a non-in-plane EM wave at around an operation frequency associated with said EM wave polarizing structure and outputs a polarized EM wave. 
 
     
     
       2. The EM wave polarizing structure of  claim 1 , wherein said non-in-plane EM wave is non-polarized or partially polarized and said polarized EM wave is one of TE polarization and TM polarization. 
     
     
       3. The EM wave polarizing structure of  claim 1 , wherein said non-in-plane EM wave is polarized into said EM wave with one of TE polarization and TM polarization in accordance with said operation frequency. 
     
     
       4. An electromagnetic (EM) wave polarizing device, comprising:
 an EM polarizing structure according to  claim 1 , wherein said photonic unit cells have a photonic crystal band structure, in which said operation frequency is selected close to one of frequency bands of said photonic crystal band structure; and 
 a non-in-plane EM wave emitting source structure associated with said EM polarizing structure emitting said non-in-plane EM wave at around said operation frequency, 
 wherein said EM wave polarizing structure processes said non-in-plane EM wave and said device thus outputs said polarized EM wave. 
 
     
     
       5. The EM wave polarizing device of  claim 4 , wherein said polarized EM wave is one of TE mode polarization and TM mode polarization. 
     
     
       6. The EM wave polarizing device of  claim 4 , wherein said frequency bands at around said operation frequency are sufficiently separated, and each of said frequency bands has a corresponding polarization state. 
     
     
       7. The EM wave polarizing device of  claim 4 ,
 wherein the non-in-plane EM wave emitting source structure is a visible light emitting device and is integrated with said EM polarizing structure, wherein said EM polarizing structure is part of said light emitting device. 
 
     
     
       8. The EM wave polarizing device of  claim 4 , wherein said medium nodes are holes or holes filled with a material, and the material is at least one selected from the group consisting of dielectric substance, organic substance, metal, solid substance, holes polymer, stacked layers of solids, and holes liquid. 
     
     
       9. The EM wave polarizing device of  claim 4 , wherein said medium nodes are posts or posts made up of a material, and said material is at least one selected from the group consisting of dielectric substance, organic substance, metal, solid, polymer, stacked layers of solids, and liquid. 
     
     
       10. The EM wave polarizing device of  claim 4 , wherein said medium node on said plane is in a shape, and said shape is one selected from the group consisting of circle, triangle, square, rectangle, ellipse, pentagon, and complex pattern. 
     
     
       11. The EM wave polarizing device of  claim 4 , wherein a refractive index of said medium node is different from that of a surrounding background medium. 
     
     
       12. The EM wave polarizing device of  claim 4 , wherein a center of each of said photonic unit lattice cells further comprises at least a central medium node. 
     
     
       13. The EM wave polarizing device of  claim 4 , wherein a depth of said medium node is greater than a quarter of one EM wavelength. 
     
     
       14. A method for providing polarized electromagnetic (EM) wave, comprising:
 providing an EM polarizing structure, a two dimensional planar pattern structure having medium nodes, wherein said medium nodes are regularly distributed as a plurality of planar photonic unit lattice cells being two-dimensional on a plane, each of said planar photonic unit lattice cells is identical and has an operation axis, of which direction passes a diagonal of said photonic unit lattice cell, and said medium nodes within each of said photonic unit lattice cells distributed asymmetrical with respect to said operation axis direction are identical at each lattice point, and wherein each of said photonic unit lattice cells is an in-equilateral parallelogram; and 
 using said EM wave polarizing structure to process a non-in-plane EM wave at around an operation frequency associated with said EM wave polarizing structure and outputs a polarized EM wave. 
 
     
     
       15. The method for providing polarized electromagnetic wave of  claim 14 , wherein in the step of providing said EM polarizing structure, said medium nodes are holes or holes filled with a material, and said material is at least one selected from the group consisting of dielectric substance, organic substance, metal, solid, polymer, stacked layers of solids, and liquid. 
     
     
       16. The method for providing polarized electromagnetic wave of  claim 14 , wherein in the step of providing said EM polarizing structure, wherein said medium nodes are posts or posts made up of a material, and said material is at least one selected from the group consisting of dielectric substance, organic substance, metal, solid, polymer, stacked layers of solids, and liquid. 
     
     
       17. The method for providing polarized electromagnetic wave of  claim 14 , wherein in the step of providing said EM polarizing structure, a refractive index of said medium node is different from that of a surrounding background medium.